The present invention relates generally to actuating switches for use in centrifugal pumps. The invention relates more particularly to actuating switches as commonly used in pumps partially submerged in a receiving basin or vessel which selectively operate the pump to maintain the liquid level in the vessel in a desired range.
Actuators or switches used to selectively operate pumping systems are frequently subjected to adverse conditions. Typical conditions include complete, or partial submersion of the pumping system in a liquid such as water. Over the years industry has developed a need for pump actuating systems which can withstand such conditions foe extended periods and function reliably.
Previous attempts to respond to this need have typically involved placing a sensing element remote from the pump and operably attaching the sensing element to the pump. In addition, previous solutions have incorporated isolated switches housed within protective chambers, but the switches typically incorporate complicated switching mechanisms. Some examples include switches incorporating conductive liquids and switches activated through elaborate mechanical systems. In addition, switching devices were frequently housed in multiple piece chambers which utilized gaskets and other sealing means to protect the switching elements from the environment. These sealing arrangements may be prone to undesirable leakage.
Thus, it is an object of the present invention to provide an improved actuating system for use in centrifugal pump systems which reduces the interfaces which must be sealed to isolate the switching element from the environment around the pump.
It is a further object of the invention to provide an improved actuating system for centrifugal pumps which makes use of a novel arrangement of simple mechanical switching elements.